See Also: uranium-thorium-lead dating(encyclopedia)
Debye, Peter(encyclopedia)
uranium-234-uranium-238 dating(encyclopedia)
thorium(dictionary)
Debye(dictionary)
Thorium(medicine)
thorium dioxide(medicine)
Debye sheath(medicine)
thorium compounds(medicine)
Debye sphere(medicine)

uranium-thorium-lead dating (sh) and Debye, Peter (sh)


uranium-thorium-lead dating (sh)




or common-lead Dating

Method of Dating very old rocks by means of the amount of common lead they contain.

Common lead is any lead from a rock or mineral that contains a large amount of lead and a small amount of the radioactive precursors of lead (i.e., the isotopes uranium-235, uranium-238, and thorium-232). By this method, the age of the Earth has been estimated to be งใ 4.6 billion years. This figure is in good agreement with the age of meteorites and the age of the Moon as determined independently.


Debye, Peter (sh)




orig. Petrus Josephus Wilhelmus Debije

born March 24, 1884, Maastricht, Neth.
died Nov. 2, 1966, Ithaca, N.Y., U.S.

Dutch-born U.S. physical chemist.

His first important research, on electric dipole moments, advanced knowledge of the arrangement of atoms in molecules and of the distances between atoms. He showed that X-ray crystallography worked on powders, obviating the difficult first step of preparing good crystals. In 1923 he and Erich Huckel extended Svante Arrhenius's theory of the dissociation of salts in solution, proving that ionization is complete. He also investigated light scattering in gases. He won the Nobel Prize in 1936.